A surgeon often has a variety of graft choices for replacing soft tissue in surgical reconstruction procedures. Two possible options include autografts, tissues donated from the patient's own body, and allografts, tissue harvested from a donor, often a cadaver. Autografts can be beneficial because the graft is harvested directly from the host and is aged correctly for the host. However, the added procedure required to harvest the graft from the patient can result in additional pain and an extended post surgical recovery period. In contrast, allografts can provide added benefit over autografts because they do not require the patient to recover from a bone and/or soft tissue harvesting operation. This can result in a faster healing time and a reduced amount of physical therapy following the procedure.
Allografts, unlike organ transplants, do not usually pose a risk for rejection by the host and, after being harvested from a cadaver, they can be cleaned and frozen in liquid nitrogen for later use. Further, a cadaver can be screened for any illness which can be transferred to the host prior to harvesting any tissue or bone. However, the quality of an allograft is not always guaranteed. In the case of bone, for example, the quality of a graft can be dependent on the age and density of the bone being harvested. Additionally, chemical sterilization, irradiation, and other processing can compromise the quality of the bone.
Anterior Cruciate Ligament (ACL) repair is one example of a procedure where allografts are commonly utilized. Typically, a surgeon can replace a damaged ACL with a bone-tendon-bone (BTB) allograft taken from a cadaver's patellar tendon or other tissue. As shown in FIG. 1, the procedure generally requires preparing a patient's knee for ACL reconstruction by forming two bone tunnels 6, 8, one in the tibia and one in the femur. The BTB allograft 1 can be drawn first through the tibial tunnel 6 and the femoral tunnel 8 such that one bone plug can be secured within the tibia and the other can be secured within the femur. The surgeon can draw the BTB allograft 1 through the tibial and femoral tunnels by pulling on a suture that is threaded through the tunnels and a bore formed in the leading bone plug.
If the quality of the leading bone plug is poor, however, the suture can pull through the bone plug during implantation. This is because the narrow suture contacts the bone plug over a small area, and therefore imparts significant pressure onto the bone plug when a surgeon or other user pulls the graft through the tunnels 6, 8.
Accordingly, there is a need for improved devices and methods for reinforcing tissue grafts. More particularly, there is a need for improved bone plug reinforcement devices for use with tissue allografts.